A year of race against time to find Covid-19 vaccines, hope is near

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Paris: The world is close to producing a vaccine against the Covid-19 epidemic, only a year after the emergence of this new disease, in a goal that has been achieved thanks to research that has been carried out at record speed, although many questions remain.

When does the vaccine become available on hand?

November was a defining month when manufacturers made their first announcements about the effectiveness of the vaccines they were working on.

In Europe, the European Medicines Agency confirmed Monday to Agence France-Presse that it may give the license for the first vaccinations before the end of the year or early 2021. On the basis of these dates, many countries have drawn up their plans in recent days, such as Spain, Italy and France.

The United States, for its part, hopes to start a vaccination campaign in mid-December, once the FDA has obtained a license.

The Chinese authorities, in turn, have given the green light for the emergency use of some vaccines that their companies have manufactured.

This advancement in the field of vaccines was made possible by an acceleration on all fronts of research, industrial production and evaluation, backed by massive funds. It usually takes ten years to develop and launch a new vaccine on the market.

The European Medicines Agency stresses that “the same regulatory standards related to quality, safety and efficacy are based on the vaccines against Covid-19”.

However, whatever the date of official approval for vaccines, not all of the Earth’s population will not be vaccinated all at once.

The Director-General of the World Health Organization, Tedros Adhanom Ghebreyesus, said recently that “in the first stage, the quantities of the vaccine will be limited and the priority will be for the most vulnerable groups.”

Another important dilemma that will be posed in this context is equality between poor and rich countries in obtaining vaccines.

As for Gebresus, “vaccines were developed urgently, and their equitable distribution must also be an urgent matter,” adding on Monday that the poor and most vulnerable countries “face the danger of being ignored in the midst of the influx of vaccines.”

Which vaccine is best?

It is not possible to answer this question at this time. Since November 9, four manufacturers have declared their vaccines effective: the US-German alliance Pfizer / Biontech, the American laboratory Moderna, the British Alliance AstraZeneca / Oxford, and the Russian State Institute of Gamalia.

Despite this advertising race that gave impetus to global stock exchanges, the numbers were only revealed in press releases, and without publishing detailed scientific data.

The results depend on the final or third phase of a clinical trial, which has undergone tens of thousands of volunteers. Effectiveness is measured by comparing the number of people who contracted the disease in the group that received the vaccine, to those who contracted it in the group that received the fake vaccine.

It was revealed after a predetermined number of volunteers fell ill: 170 for Pfizer / Biontec, 95 for Moderna, 131 for AstraZeneca / Oxford, and 39 for the Gamalia Institute.

The effectiveness of the Pfizer / Bionic vaccine was 95%, as of the 170 infected, only 8 were from the vaccinated group, and 162 from the group that did not receive the vaccine.

The efficacy of Moderna vaccine was 94,5% (5 patients from the group that received the vaccine, 90 from the group that received the fake vaccination).

The effectiveness of the Russian “Sputnik-V” vaccine is 91.4% compared to the number of 39 patients, and 95% compared to the number of patients that have not been identified.

The calculations adopted by AstraZeneca / Oxford are more complicated. The vaccine’s effectiveness rate is an average of 70%, if the results of two different protocols are combined.

The effectiveness was 90% in volunteers who received an initial half dose, then a full dose a month later. The percentage drops to 62% for the range of another group, which received two full doses, a month apart between the first and the second. This indicates that the first vaccination method achieved a better immune response.

However, effectiveness is not all that counts. AstraZeneca vaccine is the cheapest (about € 2.50 a dose). As for the Moderna and Pfizer / Biontec vaccines, they have no logistical obstacles, because the technology used to manufacture them requires long-term storage at very low temperatures (minus 20 Moderna and minus 70 degrees for Pfizer).

What are the unanswered questions?

Many questions remain.

The Director-General of the Health Organization warned that “the vaccine will complement other means in our possession, and will not replace them,” even if “the light at the end of the tunnel has become stronger.”

The most important question relates to the long-term effectiveness of the vaccine, because the accounts issued were prepared only two weeks after the volunteers received the last dose.

British expert Benny Ward from King’s University in London, as quoted by the Science Media Center, wonders, “How long does the protection last? Will the virus be able to transform to evade the vaccine, which will thus limit the effectiveness of vaccination?”

Another basic question that arises: It is not clear yet whether the vaccine interacts in the same way with the most vulnerable population group, starting with elderly people who have a weak immune system. They are more susceptible to serious forms of the disease, and therefore it is important that the vaccine is useful to them.

Finally, it remains to know whether the vaccine prevents transmission of the infection, in addition to reducing the severity of the disease among those who received it. This is a very essential point to stop the epidemic.

Experts believe that in this area AstraZeneca / Oxford has an advantage over other vaccines.

“Contrary to what happened in other experiments, the AstraZeneca / Oxford team examined all participants every week for symptom-free injuries,” said Academy Eleanor Reilly from the University of Edinburgh, as quoted by the Science Media Center.

For its part, Oxford University confirmed, “We have initial indications that the vaccine is able to prevent the transmission of infection, because a decrease in the number of asymptomatic infections has been observed.”

In an interview with France Press, AstraZeneca said that the systematic detection of asymptomatic patients does not concern all of the 23,000 volunteers, but only a part of them, without announcing the intended number.

Finally, if the trials do not show any serious side effects, it is necessary to carry out a “continuous follow-up” process to ensure that “there are no rare, unwanted but more dangerous effects when the vaccine is used on a larger scale,” according to Dr. Ward.

How many vaccines are offered?

Among the four vaccines that have reached an advanced stage, 11 are in the third phase of trials, according to the latest WHO announcement in this regard, dated November 12.

Among them, many projects of Chinese laboratories (such as Sinophac, Cinopharm, and Cansino).

In total, there are 48 “candidate vaccines” being tested on humans around the world. In addition to 11 vaccines in the third trial phase, there are 37 in the first phase (which aims to assess the safety of the product) and the second (which studies its effectiveness).

In addition to those that have already entered the testing phase, the WHO is counting 164 vaccine projects in the pre-clinical phase.

What techniques are used?

Laboratories used different methods, some tried and new.

Multiple teams are working with traditional means, such as the technique of the “inactive” vaccine that develops with a virus whose infectious agents have been treated, and it is the technique used by Chinese Sinovac and Sinopharm.

There are also recombinant proteins vaccines, which are based on creating an immune response through proteins and not via a virus.

As well as the technology of vaccines with “viral vectors”, which is more advanced, as it takes as a base another virus that is being transformed and adapted to combat Covid-19. AstraZeneca / Oxford is working with this technology, as are the Russians who are based on developing an adenovirus vaccine.

Finally, more technically advanced projects are relying on “DNA” or “messenger RNA” vaccines. This technology is based on pumping molecules of genetic instructions into cells, to push them to manufacture proteins or “antagonists” directed against the Corona virus. Moderna and Pfizer / Pinotech are working with this technology.

Will people trust the vaccine?

Whatever the first dates of vaccination campaigns, a fundamental question remains, which is will people accept to receive the vaccine in the context of a significant increase in mistrust?

According to a study published in mid-October in the British journal “Royal Society Open Science”, a good portion of the population in some countries believes in conspiracy theories related to Covid-19, which increases their distrust of the vaccine.

For example, 22% of Mexicans surveyed in this study believed the validity of the false idea that the epidemic “is part of a plan to impose global vaccination.”

An investigation published in early November by the World Economic Forum and conducted in 15 countries showed that the proportion of people prepared to receive the vaccine decreased compared to August.

Only 73% support the following statement: “If a vaccine against Covid-19 is available, I will be vaccinated,” compared to 77% in August.

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